Self-loading device for trailers of logging trucks



ch 24, 1936. w. G. STRATTON 2,034,842

SELF LOADING DEVICE FOR TRAILERS OF LOGGING TRUCKS Filed Feb. 11, 1935 2Sheets- Sheet 1 FIE|1| EIEu IE.

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arch 24, 1936. w STRATTQN 2,034.842

SELF LOADING DEVI :E FOR TRAILERS OF LOGGING TRUCKS Filed Feb. 11, 19352 Sheets-Sheet 2 m WIDM MN mN @w IZYYE'ZYTORI 1 1 76, STRHTTON. Q dim/zTTORNE Y5.

Patented Mar. 24, 1936 UNITED STATES PATE ' OFFIE SELF-LOADING DEVICEFOR TRAILERS OF LOGGING TRUCKS 3 Claims.

This invention relates to improvements in selfloading devices fortrailers of logging trucks.

The principal object is to produce a logging truck trailer connectionwhich will automatically eifect a loading of the trailer onto itsattached truck for return movement when the trailer is being returnedempty to the point of loading.

Another object is to produce a device wherein the weight of the trailerautomatically unloads the trailer from the truck when released.

A further object is to produce a device which may be actuated from thedrivers compartment of the truck.

A still further object is to produce a device. which is sturdy inconstruction, economical to manufacture and readily applicable tostanda-.d trucks and trailers.

Other objects and advantages will be apparent during the course of thefollowing description.

In the accompanying drawings forming a part of this specification and inwhich like numerals are employed to designate like parts throughout thesame,

Fig. 1 is a side elevation of a truck and trailer having my inventionapplied thereto,

Fig. 2 is a top plan view of Fig. 1,

Fig. 3 is a cross sectional view on the line 33 of Fig. 2,

Fig. 4 is a fragmentary view showing the manner in which the trailerconnection hinges,

Fig. 5 is a fragmentary view showing the trailer in loaded position onthe truck,

Fig. 6 is an enlarged detail view of the latch mechanism, and

Fig. '7 is a cross sectional view taken on the line 'II of Fig. 6.

In the handling of long objects, such as logs, pipes, and the like, itis common to employ a twowheel trailer connected to the truck by atongue pivoted to a king-pin upon the rear of the truck. In this mannerthe long objects extend between the trailer and the truck and pivotabout the king-pin on the truck. After unloading such trailers it iscommon practice to load the trailer on the truck for transportation backfor a second load. This is usually accomplished by main force as thesetrailers are heavy and very unwieldly. Much breakage occurs throughrough handling and injuries also result incidental to the manipulation.I have, therefore, devised an arrangement which obviates thesedifficulties.

Referring to Fig. 1, the numeral 5 designates the truck frame ofstandard construction, upon which I mount a. platform 6 and to which issecured the king-pin I. This construction is common and forms no part ofmy invention.

A bolster is shown at 8 to which I connect a yoke 9, which carries thepintle II of a hinged channel member I2. This channel member is sopositioned that its webs I3 extend downwardly when in the pcxsition ofFig. l. The numeral I 4 designates a two-wheel trailer as a whole, towhich is connected a tongue I6 and it is to this tongue that I attach alatch-box which consists of side plates I'I bolted or otherwise securedto the tongue I6 and projected therefrom. This latch-box has a bottomplate I8 and cross piece I9, which cross piece extends between the sideplates II. E);- tending between one of the cross pieces I9 and thebottom plate I8 is a pivot pin 2 I, to which a lever 22 is pivoted. Thislever has bolts 23 and 24 connected thereto on opposite sides of thepivot 2|. A spring 25 tends to normally keep these bolts projectedthrough the plates I I as will be later described.

A cable 21 is connected to the lever 22 in such a manner as to overcomethe tension of the spring 26 so as to retract the bolts 23 and 24. Thiscable extends to the drivers compartment. A pivot pin 28 connects thelatch box with the channel member I2. Secured to the trailer are plates29 so arranged that they underlie the forward portion of the springs ofthe trailer, and are capable of engaging arms 3| secured to the rear ofthe trailer, the operation of which will be later seen. An opening 32 isformed on each side of the channel member, one forward of the pivot 28and one rearward thereof, so that the bolts 23 and 24 will alternatelyengage these openings when the device is in open or closed position.Recesses 33 are formed in the channel I2 and in alignment with theopening 32 so that free movement of the respective bolts may take placein the manner to be described.

The operation of my device is as followsz-Assuming that the parts are inthe position of Fig. 1, then the bolt 23 will be engaging its opening 32(see Fig. 6), and consequently the hinged joint between the channelmember and the tongue will be locked. Let us now assume that the loadhas been delivered and it is desired to move the trailer onto the truck,the operator pulls the cord 2'! against the tension of the spring 26.This withdraws the bolt 23 from the opening 32 and it is to be herenoted that the bolt 24 was at this time lying within one of the recesses33. By now backing the truck and trailer against a chock A, which isbelow the axle of the trailer, the trailer will tip backwardly asillustrated in Fig. 3, breaking the joint and causing a folding action.This will bring the arms 3| into engagement with the plates 29 and causea lifting action of the trailer. At this time the channel member willhave moved to the position of Fig. 5 and the bolt 24 will move into itsopening 32 and the bolt 23 will lie in its recess 33. When it is desiredto unload the trailer, the operator merely pulls upon the cord 21 andthe weight of the trailer which is unsupported will slide on the arms3|, causing the channel member and tongue to move from the position ofFig. 5 to that of Fig, 4 and then Fig. 1, where it will automaticallylook into loading position.

It will thus be seen that I have produced a device which will accomplishall the objects above set forth.

It is to be understood that the form of my invention herewith shown anddescribed is to be taken as a preferred example of the same and thatvarious changes relative to the material, size, shape and arrangement ofparts may be resorted to without departing from the spirit of theinvention or the scope of the subjoined claims.

Having thus described my invention, I claim: 1. In combination with atruck and a trailer having a tongue secured thereto, of a channel memberpivotally secured to said truck and to said tongue, latching meansconnecting said tongue to said channel member, said latching meansholding said tongue in parallel alignment with said channel member whenmoved above said pivot in either of two positions substantially 180apart.

2. In combination with a truck and a trailer having a tongue securedthereto, of a channel member pivotally secured to said truck and to saidtongue, latching means connecting said tongue to said channel member,said latching means holding said tongue in parallel alignment with saidchannel member when moved above said pivot in either of two positionssubstantially 180 apart, said latching means comprising a pair of boltspivoted for simultaneous actuation and so positioned as to extend intothe side webs of said channel mechanism.

3. In combination with a truck and a trailer havinga' tongue securedthereto, of a channel member pivotally secured to said truck and to saidtongue, latching means connecting said tongue to said channel member,said latching means holding said tongue in parallel alignment with saidchannel member when moved above said pivot in either of two positionssubstantially 180 apart, said latching means comprising a pair of boltspivoted for simultaneous actuation and so positioned as to extend intothe side webs of said channel mechanism, and supporting means extendingfrom said truck to underlie and support said trailer when said traileris mounted on said truck.

WILLIAM G. STRATTON.

